DIPOL Weekly Review – TV and SAT TV, CCTV, WLAN

Are we in for a revolution in photography?

French startup Prophesee has partnered with Qualcomm to introduce a new type of image sensor that will enable cameras and camcorders to capture fast-moving images.

Named Metavision, the technology works in tandem with traditional cameras, supplementing the image with information about changes that occur in the scene. It aims to solve the problem of image blur that often occurs when photographing subjects in motion. An example would be a shot of a tennis player during the bounce of a ball, which would be blurred or invisible in a standard photo. Metavision combines the data from the event camera with the traditional image and the image processing algorithm fills in the gaps, repairing the blur caused by the subject's movement.

The Metavision image sensor mimics the human visual system. Unlike traditional image sensors, which capture an image every fixed time interval, each pixel in the system operates independently, responding to changes in light intensity. These changes are detected asynchronously and transmitted along with information about the pixel's position (x and y coordinates) and time. The light-sensitive pixels are directly connected to a logic core that analyses the light intensity changes of individual pixels. This ensures that data is only generated for the points where the change has occurred. This makes it possible to transmit high temporal resolution data with low latency and low power consumption. The new camera achieves a speed equivalent to 10,000 frames per second. A standard camera, in order to achieve this speed, would require very intensive lighting and would generate huge amounts of data. With the Metavision camera, no strong lighting is needed and the amount of data generated depends on the amount of movement but is much smaller.

Event cameras also have industrial applications and can be used to observe various processes and to count fast-moving objects, such as the number of tablets being machine-packed into a package. They have many advantages over current solutions. They operate correctly even in low-light conditions, generate small amounts of data, while consuming little energy and being relatively inexpensive. However, it is necessary to provide suitable operating conditions for these cameras. Event cameras only record changes in brightness, such as an increase or decrease, which can be caused by both, the movement of objects and changes in the lighting of the scene or the movement of the camera itself.

TV system in a hotel.

Transmodulators that convert the DVB-S/S2 signal to DVB-T COFDM are a popular solution used in many hotels. Satellite channels can be an addition to the terrestrial television programs or be the only part of the package offered. The digital DVB-T COFDM signal available at the output is usually delivered to the end receivers using splitters / splitters.

Use of relay outputs in the DS-KH6320-WTE1 Hikvision IP video intercom monitor.

When installing a video-intercom system, it is sometimes necessary to install additional functions to notify the user that someone has pressed the call button on the door station. An example can be installation of the system in a noisy production hall, using it by a person with impaired hearing or a need to install signalling outside the house, so that being in the garden you would notice that someone has come.

The DS-KH6320-WTE1 video-intercom monitor has two built-in relays that can be activated when the monitor starts ringing after the call button is pressed. These relays can operate in monostable (1-180 s) or bistable mode. The operating time and mode of each relay can be configured individually. For example, one relay can be connected to an buzzer with an operating time of 5 s and another to a visual indicator with an operating time of 60 s. Pairing the relays with a call button can be done using the iVMS-4200 application, after entering the remote settings of the monitor in the tab: Intercom -> Calling Linkage. Select the Enable option and choose the relay output that will be activated at the moment of calling. The relay mode and time setting can be configured directly from the monitor.

PoE power supply for 250 m – "Extend" function.

The ULTIPOWER 0064afat N29978 PoE switch is a desktop device for smooth network transmission. It has 6 RJ45 ports supporting automatic connection speed negotiation. Four of them support the Power over Ethernet (PoE). The switch automatically detects PD devices compliant with IEEE 802.3af or IEEE 802.3at and supplies them. This makes it possible to extend the range of the network to locations with no access to power lines or outlets, and where access points, IP cameras, IP phones, etc. have to be located. The maximum total power of the devices supplied must not exceed 65 W.

The switch has the "Extend mode function "(activated by the switch on the enclosure) for PoE powering of devices connected via up to 250-meter section of twisted-pair cable. When activated, the switch on the PoE ports disables autonegotiation of connection speed and firmly sets the speed to 10 Mbps (the uplink ports continue to operate at 10/100 Mbps).

What is the life expectancy of electrodes in fibre optic splicers?

Electrodes in fibre optic splicers are a consumable components subject to cleaning and periodic replacement. The frequency of replacement depends directly on the number of splices performed. The electrodes available on the market vary in material, with tungsten electrodes being the predominant material, although these can also vary in terms of the tungsten content of the alloy. This results in a different service life of 2,500 to 5,000 spllices.

Splicer manufacturer Signal Fire specifies an electrode life to be 3,000 splices. Note, however, that the condition of the electrodes is also affected by the arcs generated during the calibration process of the splicer, and these are not counted by the splice counter. Therefore, the final lifetime of electrodes in a splicer that makes several hundred splices in 1 welding cycle may look different from when several hundred splices are performed in several dozen cycles (during which an arc calibration is performed each time). Note that Signal Fire splicers come with a second set of electrodes.

Fiber optics in CCTV – PoE switch in a RACK cabinet. CCTV systems that are currently being built are often based entirely or partially on fiber optic cabling. The distinctive feature of such systems is the place where multi-pair cabling from CCTV cameras converges at the point of installation of a network switch (which also acts as PoE power supply for the cameras) and where one or more fiber optic cables have their terminations. From there, the signal is transmitted to a DVR located in another location or to another segment of the network...>>>more